Liquid jet recording head and recording apparatus having same

ABSTRACT

A process is disclosed for producing a liquid jet recording head comprising applying an active energy-curing resin composition onto at least a part of a surface of a first member for forming a wall of the liquid path; exposing the applied active energy-ray-curing resin to an active energy ray selected from the group consisting of an ultraviolet-ray having an intensity of 1 mW/cm 2  to 100 mW/cm 2  and an electron beam having an intensity of 0.5M Rad to 20M Rad; and providing a second member on the exposed active energy-ray-curing resin composition.

This application is continuation of application Ser. No. 08/267,311filed Jun. 29, 1994, now abandoned, which is a continuation of Ser. No.08/022,404, filed Feb. 24, 1993, now abandoned, which is a continuationof application Ser. No. 07/494,096, filed Mar. 21, 1990, now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a liquid jet recording head and a recordingapparatus by use thereof, particularly to a liquid jet recording head tobe used for the liquid jet recording system which performs recording bydischarging liquid for recording such as ink, and the like to attach itonto a recording medium such as paper, and a recording apparatus by usethereof.

2. Related Background Art

The liquid jet recording system which performs recording by dischargingliquid for recording such as ink and the like to attach it onto arecording medium such as paper is extremely small to negligible extentin generation of noise during recording, and also enables high speedrecording. Yet, it is attracting attention as the recording systemcapable of performing recording on a plain paper without requiring aspecial treatment such as fixing, and various types have been recentlyactively studied.

The recording head of the recording apparatus to be used in the liquidjet recording system is generally constituted by having an orifice(discharge opening) for discharging liquid for recording, a liquid pathcommunicated with the orifice and having a portion at which the energyfor discharging liquid for recording acts on the liquid for recording,and a liquid chamber for storing the liquid for recording to be suppliedto the liquid path.

The energy for discharging the liquid for recording during recording ismostly generated by a discharge energy generating element of varioustypes such as heat-generating element, a piezoelectric element arrangedat a predetermined position of the portion (energy acting portion) wherethe discharge energy is acted on the liquid for recording constituting apart of the liquid path.

As the method for preparing a liquid jet recording head of suchconstitution, there may be included, for example, the method includingthe steps of forming a fine groove on a flat plate such as of glass,metal, and the like by cutting, etching, and the like and furtherforming a liquid path by bonding another appropriate plate to the flatplate having such groove formed thereon to form a liquid path, or themethod including the steps of forming a wall of a photosensitive resincured on a substrate having, for example, a discharge energy generatingelement arranged thereon by photolithographic step to provide a groovewhich becomes the liquid path on the substrate and bonding another flatplate (cover) to the grooved plate thus formed to form a liquid path(for example, U.S. Pat. No. 4,417,251).

Among these methods for preparation of liquid jet recording head, thelatter method of employing a photosensitive resin can finely work theliquid path with better precision, and with better yield, as comparedwith the former method, and also bulk production can be realized moreeasily, and therefore it has the advantage that a liquid jet recordinghead with better quality and lower cost can be provided.

As the photosensitive resin for preparation of such a recording head,there have been used those which have been used for pattern formation inprinting plate, print wiring, and the like, those known as the coatingmaterial or adhesive of the photocurable type to be used for glass,metal, ceramics, etc., and also primarily resins of the dry film typefrom the aspect of working efficiency.

In the recording head utilizing a cured film of a photosensitive resinfor a part of the constitution, for obtaining excellent characteristicssuch as high degree of recording characteristic, durability andreliability, and the like, the photosensitive resin to be used isrequired to have such characteristics as:

(1) particularly excellent adhesion to the substrate, etc. as the curedfilm;

(2) excellent mechanical strength and durability when cured;

(3) excellent sensitivity and resolution during patterning by use ofpattern exposure.

Whereas, few of the known photosensitive resins which have been employedfor formation of liquid jet recording heads up to date fully satisfiedall of the characteristics as mentioned above under the presentsituation.

As the photosensitive resin for recording heads, for example, thoseemployed for pattern formation in printing plate, print wiring, etc.,although excellent in sensitivity and resolution, are not satisfactoryin such demands as adhesion and close contact with glass, ceramics,plastic films, etc. used as a substrate in most cases, and alsosometimes insufficient in mechanical strength or durability when cured.For this reason, in the step of preparing a recording head or asaccompanied with use of a recording head, there may sometimes ensue suchproblem that deformation, peel-off from the substrate, damage of theresin cured film which may be a cause for remarkable damage of thereliability of the recording head such as lowering in recordingcharacteristics by inteference of the flow of the liquid for recordingwithin the liquid path, or making the liquid discharge directionunstable.

On the other hand, those known as the photocurable type coating materialor adhesive to be used for glass, metal, ceramics, etc., although havingsuch advantages that they are excellent in close contact or adhesionwith the substrates comprising these materials, and also that sufficientmechanical strength and durability are obtained when cured, are notsatisfactory in the demands of sensitivity and resolution in most cases,whereby an exposure device of higher intensity or prolonged exposureoperation are required. Also, in their characteristics, no highlyprecise high density pattern can be hardly obtained with goodresolution, and therefore such resins have the problem that they are notsuitable for recording heads for which fine precise working isparticularly required.

Also, in the photosensitive resin compositions utilized for various usesof the prior art, adhesion with metal, etc. has been improved byaddition of various additives such as heterocyclic compounds havingcomplex forming ability with metals, etc., or coupling agents, etc. intothe photosensitive resin composition (Japanese Patent Publication Nos.51-5934, 58-24035, etc.). However, this method had the problem that theabove additive aids, etc. caused such phenomena as oxidation andcorrosion of the composition, etc. after elapse of a long term.

On the other hand, for the purpose of obtaining a cured compositionhaving sufficient adhesion without addition of such additive aids, apolymeric substance comprising a graft copolymer having polar group inthe branched chains is disclosed in Japanese Laid-open PatentApplication Nos. 61-283645, 61-283646. The active energy-ray-curingresin composition containing the polymeric substance (graftcopolymerized polymer) disclosed in the applications has the advantagethat improvement of adhesion, further improvement of durability of thecoating can be realized without relying on additive aids, etc.

However, in this composition, there still remained the problem thatdifficulty is accompanied with the molecular design of the polymericsubstance (graft copolymerized polymer). More specifically, there isgenerally accompanied technical difficulty in synthesizing a graftcopolymer so that its whole weight average molecular weight may become asuitable desired molecular weight over a wide range (about 50,000 to350,000) while maintaining the molecular weight of the graft chain andits content at constant levels.

Shortly speaking, for making good the developing characteristics duringpattern formation, namely dissolving rate of the unpolymerized portion,swellability of the polymerized portion, and sensitivity, sharpness ofpattern, resolution as the results of them, the average molecular weightof the polymeric substance must not be too small. In the graftcopolymerized polymer, it is accompanied with difficulty from the pointof steric hindrance in the synthetic technique at the present time toobtain an average molecular weight in conformity with theabove-mentioned object by bonding a large number of graft chains havingenough lengths to obtain effective adhesion to the trunk chain of arelatively larger molecular weight.

In other words, if the average molecular weight of the polymericsubstance is too low, the developing characteristics of the patternforming material by use thereof, namely dissolving rate of theunpolymerized portion, swellability of the polymerized portion, andsensitivity, sharpness of pattern, control of resolution are limited tosome extent.

Thus, the photosensitive resin composition to be used as the constituentmaterial of a liquid jet recording head (ink jet recording head) isrequired to have characteristics of extremely high performance.

Specifically, the characteristics demanded for the photosensitive resincomposition may be mentioned as follows:

(1) The composition should be such that when formed into a cured film,the film is completely or substantially free from dissolution into ink,and should not cause problems such as generation of a foreign matterwhich may cause clogging of discharge opening or liquid path or changein discharge characteristics by change in ink properties;

(2) The composition should be such that when formed into a cured film,the film causes no lowering in strength or change in dimensions as thestructural material such as swelling, peel-off, generation of cracks bypenetration of ink;

(3) The composition should be such that when applied as a cured film toa recording head in which particularly, heat energy is utilized as theliquid discharging energy, there occurs no deformation of the shape,etc. by the pressure for liquid discharging and the thermal shock andthe like.

This is because the photosensitive resin composition (or its curedproduct) is constantly in contact with ink (water-soluble organicsolvents of high polarity are used therein in most cases), whereby theproblem will readily occur that residual soluble components aredissolved into ink.

Also, lowering in strength, change in dimensions as the structuralmaterial, in addition to giving great restrictions in design of ink, addgreat restrictions in durability, design of the recording head itself.

Further, due to the synergetic action of heat and pressure, there may besometimes generated such problems as deformation, etching, etc. as thestructural material.

SUMMARY OF THE INVENTION

The present invention has been accomplished in view of the problems asdescribed above, and its object is to provide a recording head by use ofan active energy-ray-curing resin composition, having sufficientadhesion without addition of additive aids, etc., excellent developingcharacteristics during pattern formation, and also characteristicsreadily controlled so as to give good characteristics as the constituentmember of a liquid jet recording head, which is inexpensive and highlyprecise, high in reliability and excellent in durability, and arecording apparatus by use thereof.

Another object of the present invention is to provide a liquid jetrecording head having a constitution with a liquid path finely workedwith good precision and with good yield, and a recording apparatus byuse of the head.

Still another object of the present invention is to provide a liquid jetrecording head having high reliability and excellent durability alsowhen formed into a multi-orifice, and a recording apparatus by use ofthe head.

Still another object of the present invention is to provide a recordinghead by use of an active energy-ray-curing resin composition which, whenformed into a cured film, is completely or substantially free fromdissolution into ink, and does not cause problems such as generation ofa foreign matter which may cause clogging of discharge opening or liquidpath or change in discharge characteristics by change in ink properties,and a recording apparatus by use of the head.

Still another object of the present invention is to provide a recordinghead by use of an active energy-ray-curing resin composition which, whenformed into a cured film, causes no lowering in strength or change indimensions as the structural material such as swelling, peel-off,generation of cracks by penetration of ink as the cured film, and arecording apparatus by use of the head.

Still another object of the present invention is to provide a recordinghead by use of an active energy-ray-curing resin composition which, whenapplied as a cured film to a recording head in which particularly, heatenergy is utilized as the liquid discharging energy, there occurs nodeformation of the shape, etc. by the pressure for liquid dischargingand the thermal shock and the like, and a recording apparatus by use ofthe head.

Still another object of the present invention is to provide a liquid jetrecording head comprising a cured product of an active energy-ray-curingresin composition as at least a part of its constitution, saidcomposition comprising:

(A) a graft copolymerized polymer having a number average molecularweight of 5,000 or more and a weight average molecular weight of 50,000or less which comprises a trunk chain composed mainly of structuralunits derived from at least one monomer (hereinafter referred to as"monomer (a)") selected from the group consisting of alkylmethacrylates, acrylonitrile and styrene and has graft chains havingstructural units derived from at least one monomer (hereinafter referredto as "monomer (b)") selected from the group consisting of the monomersrepresented by the following formula x and other monomers presented bythe formula y: ##STR1## (wherein R¹ is hydrogen or an alkyl orhydroxyalkyl group having 1 to 3 carbon atoms, R² is hydrogen or analkyl or acyl group having 1 to 4 carbon atoms which may have hydroxygroup, R³ is an alkyl group having 2 to 6 carbon atoms, ahalogen-substituted alkyl group having 2 to 6 carbon atoms, analkylether group represented by the formula: ##STR2## (wherein 2≦m+n≦6,n≠0 and m≠0) , or a phenylalkyl group represented by the formula:##STR3## (wherein 2≦m+n≦4 or the case where n=0 or m=0 is contained),added to said trunk chain;

(B) a linear polymer having a number average molecular weight of 50,000or more and a weight average molecular weight of 350,000 or less andhaving a glass transition temperature of 60° C. or more which comprisesstructural units derived from at least one monomer (hereinafter referredto as "monomer (c)") selected from the group consisting of methylmethacrylate, ethyl methacrylate, isobutyl methacrylate, t-butylmethacrylate, benzyl methacrylate, acrylonitile, isobornyl methacrylate,isobornyl acrylate, tricyclodecaneacrylate, tricyclodecane methacrylate,tricyclodecaneoxyethyl methacrylate, styrene, dimethylaminoethylmethacrylate and cyclohexyl methacrylate and other structural unitsderived from at least one monomer (hereinafter called monomer (b'))selected from the group consisting of the monomers represented by theformula (x) and the monomers represented by the formula (y) providedthat the monomer (a) and the monomer (b') may have either the samecomposition or different compositions;

(C) an epoxy resin which contains at least one compound having one ormore epoxy groups in one molecular;

(D) a monomer having an ethylenically unsaturated bond; and

(E) a polymerization initiator capable of generating a Lewis acid withirradiation of an active energy ray.

Still another object of the present invention is to provide a liquid jetrecording apparatus comprising a liquid jet recording head having adischarge opening for discharging recording liquid, a driving circuitfor driving said recording head and platen, said liquid jet recordinghead comprising a cured product of an active energy-ray-curing resincomposition as at least a part of its constitution, said compositioncomprising:

(A) a graft copolymerized polymer having a number average molecularweight of 5,000 or more and a weight average molecular weight of 50,000or less which comprises a trunk chain composed mainly of structuralunits derived from at least one monomer (hereinafter referred to as"monomer (a)") selected from the group consisting of alkylmethacrylates, acrylonitrile and styrene and has graft chains havingstructural units derived from at least one monomer (hereinafter referredto as "monomer (b)") selected from the group consisting of the monomersrepresented by the following formula x and other monomers presented bythe formula y: ##STR4## (wherein R¹ is hydrogen or an alkyl orhydroxyalkyl group having 1 to 3 carbon atom, R² is hydrogen or an alkylor acyl group having 1 to 4 carbon atoms which may have hydroxy group,R³ is an alkyl group having 2 to 6 carbon atoms, a halogen-substitutedalkyl group having 2 to 6 carbon atoms, an alkylether group representedby the formula: ##STR5## (wherein 2≦m+n≦6, n≠0 and m≠0) , or aphenylalkyl group represented by the formula: ##STR6## (wherein 2≦m+n≦4,or the case where n=0 or m=0 is contained), added to said trunk chain;

(B) a linear polymer having a number average molecular weight of 50,000or more and a weight average molecular weight of 350,000 or less andhaving a glass transition temperature of 60° C. or more which comprisesstructural units derived from at least one monomer (hereinafter referredto as "monomer (c)") selected from the group consisting methylmethacrylate, ethyl methacrylate, isobutyl methacrylate, t-butylmethacrylate, benzyl methacrylate, acrylonitile, isobornyl methacrylate,isobornyl acrylate, tricyclodecaneacrylate, tricyclodecane methacrylate,tricyclodecaneoxyethyl methacrylate, styrene, dimethylaminoethylmethacrylate and cyclohexyl methacrylate and other structural unitsderived from at least one monomer (hereinafter called monomer (b'))selected from the group consisting of the monomers represented by theformula (x) and the monomers represented by the formula (y) providedthat the monomer (a) and the monomer (b') may have either the samecomposition or different compositions;

(C) an epoxy resin which contains at least one compound having one ormore epoxy groups in one molecular;

(D) a monomer having an ethylenically unsaturated bond; and

(E) a polymerization initiator capable of generating a Lewis acid withirradiation of an active energy ray.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A to FIG. 6B are schematic diagrams for illustration of the liquidjet recording head of the present invention and a method for preparationthereof;

FIGS. 7A to 7H, FIGS. 10A and 10B are schematic lateral sectional viewsat the surface vertical to the liquid paths of the recording headshowing the portions in which the resin cured film is used;

FIGS. 8A and 8B, and FIG. 9 are schematic diagrams showing anotherconstitution of the recording head; and

FIG. 11 is a schematic perspective view showing an example of therecording apparatus of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The liquid jet recording head can take various constitutions as desired,but the cured product of the resin composition as mentioned above isused as at least a part of its constitution.

Referring now to the drawings, an example of the liquid jet recordinghead of the present invention is described in detail.

FIG. 1 is a preferable example of the liquid jet recording head of thepresent invention, FIG. 1A being a perspective view of its principalportion, FIG. 1B a sectional view cut along the line C--C in FIG. 1A.

The liquid jet recording head comprises basically a substrate 1, aliquid path wall 3H comprising a resin cured film patterned to apredetermined shape and a cover 7 laminated on the liquid path wall 3H,and by these members are formed an orifice 9 for discharging liquid forrecording, liquid paths 6-2 communicated to the orifice and having aportion at which the energy for discharging the liquid for recordingacts on the liquid for recording and a liquid chamber 6-1 for storingthe liquid for recording to be fed to the liquid paths. Further, to thethru-holes 8 provided at the cover are bonded feeding pipes for feedingthe liquid for recording to the liquid chamber 6-1 externally of therecording head. In FIG. 1A, the feeding pipe 10 is omitted. Of course,it may be also directly communicated through the thru-hole 8 to theinner portion of the vessel for housing the liquid for recording.

During recording, the energy for discharging the liquid for recording isgenerated by applying a discharge signal as desired on the dischargeenergy generating elements 2 of various types such as heat-generatingelement, piezoelectric element, etc. arranged at predetermined positionsof the portion where discharging energy is permitted to act on theliquid for recording constituting a part of the liquid path 6-2 throughthe wiring (not shown) connected to these elements.

The substrate 1 constituting the recording head of the present inventioncomprises glass, ceramics, plastic or metal, etc., and the generatingelements 2 are arranged in desired number at predetermined positions. Inthe example in FIGS. 1A and 1B, two generating elements are provided,but the number and arrangement of the heat-generating elements may besuitably determined depending on the predetermined constitution.

The cover 7 comprises a flat plate of glass, ceramics, plastic or metal,etc., which is bonded onto the liquid path wall 3H by the bonding methodby fusion or by use of an adhesive, and the thru-holes 8 for connectingthe feeding pipes 10 are provided at predetermined positions.

In the recording head, the resin cured film patterned to a predeterminedshape constituting the wall 3H of the liquid path 6-2 and the liquidchamber 6-1 is obtained by subjecting the layer comprising the activeenergy-ray-curing resin composition including the constituent components(A) to (E) as described above provided on the substrate 1 or on thecover 7 to patterning according to the photolithographic steps.

Having described above about an example using a cured film of the resincomposition for the constitution of the liquid path wall 3H, the curedfilm (cured product) of the resin composition can be suitably utilizedfor other portions of the recording head.

For example, as shown in FIGS. 7A to 7H represented as a partial sectionof a recording head vertical to the liquid paths, there can be mentionedutilization of:

1. as the cover 7 [FIG. 7A];

2. as the liquid path wall 3H and the cover 7 (in this case, the liquidpath wall 3H and the cover 7 may be formed integrally, or may be alsoformed separately and then bonded) [FIG. 7B];

3. as the adhesive layers 14 between the liquid path wall 3H and thecover 7 formed from various resins, etc. [FIGS. 7C, 7E and 7G];

4. as the liquid path wall 3H and the adhesive layer 14 between theliquid path wall 3H and the cover 7 [FIGS. 7D and 7F]

5. as the liquid path wall 3H and the adhesive layers 14 between theliquid path wall 3H and the cover 7 (two-layer constitution) [FIG. 7H],or a combination of them. Among the above constitutions, for formationof the constitutions of FIGS. 7A to 7E, 7H and the liquid path wall 3Hin FIG. 7F, those of the dry film type can be suitably used, while forthe adhesive layer 14 in FIGS. 7F and 7G, those of the type which isused in liquid state and cured may be suitably used.

Further, the recording head of the present invention may be also onehaving a structure for discharging liquid in the direction vertical tothe liquid path (6-2) shown in FIGS. 8A and 8B and FIG. 9, and in thatcase, for example, the cured film of the resin composition can besuitably utilized for the same portions as shown in FIG. 7, such as theportions in FIGS. 10A and 10B.

In the following, the active energy-ray-curing resin compositioncomprising the constituents (A) to (E) as mentioned above to be used inthe constitution of the recording head of the present invention aredescribed.

The resin composition, particularly when formed into a cured film, hasexcellent characteristics as a constituent member of a liquid jetrecording head such that it has good adhesion to various members such asa substrate, etc. comprising glass, plastic, ceramics, etc., and isexcellent also in resistance to the liquid for recording such as ink andmechanical strength, and yet can form a pattern which is precise and ofhigh resolution by patterning with an active energy ray.

Further, the resin composition can be also used as the dry film, andalso in that case the excellent characteristics as mentioned above canbe exhibited.

For formation of the trunk chain of the graft copolymerized polymer (A)contained in said resin composition, the monomer component (a) asdescribed above is used as the main component.

As the monomer to be used for the branched chain, in addition to themonomer component (b), polar monomers as described below are required tobe used in combination, if necessary:

(I) acrylic monomers containing amino group or alkylamino group;

(II) acrylic or vinyl monomers containing carboxyl group;

(III) N-vinylpyrrolidone and its derivatives; and

(IV) vinylpyridine and its derivatives.

In addtion, it is possible to use a hydrophobic monomer as the componentof the copolymerization in an amount of about 25 mol % or less.

The above graft copolymerized polymer (A) can be prepared according toknown methods, specifically by various methods as disclosed in "Base andApplication of Polymer Alloy" p.10-35 (edited by Polymer Society ofJapan, published by Tokyo Kogaku Dojin K. K., 1981). Examples of thosemethods include (1) the chain transfer method, (2) the method by use ofradiation, (3) the oxidation polymerization method, (4) the ion graftpolymerization method and (5) macromonomer method.

In accordance with any of these methods, the above graft copolymerizedpolymer (A) can be properly prepared using the foregoing monomers (a)and (b) under proper polymerization conditions which make it possible toobtain a desired graft copolymerized polymer having a number averagemolecular weight of 5,000 or more and a weight average molecular weightof 50,000 or less.

Among the above methods of (1) to (5), the methods of (4) and (5) arepreferred since the lengths of the graft chains may be easily uniformed.And, the macromonomer method of (5) is most preferred in view that it isadvantageous in design of materials.

The foregoing linear polymer (B) may be properly prepared in accordancewith the conventional polymerization method using the foregoing monomer(c) as the main component and also using the foregoing monomer (b')under properly selected polymerization conditions which permitproduction of a linear polymer having a number average molecular weightof 50,000 or more and a weight average molecular weight of 350,000 orless and having a glass transition temperature of 60° C. or more.

In this case, it is preferred to add the monomer (b') in an amount of 5to 30 mol % for the following reasons. That is, when more than 30 mol %of the monomer (b') is incorporated into a linear polymer to beobtained, there are disadvantages that the polar group content in acured paint film will be undesirably heightened and because of this, anyimprovement cannot be attained in its adhesiveness with a substrate, andin addition to this, the resulting cured film will be such that is poorin the water proof. On the other hand, when less that 5 mol % of themonomer (b') is incorporated into a linear polymer to be obtained, notonly the adhesiveness with substrate but also the effects of a paintfilm as the binder will be insufficient.

In order for the cured product of the resin composition to have a highglass transition temperature and to contribute in heightening the waterproof among the foregoing monomer (c), methylmethacrylate,isobonylmethacrylate, isobonylacrylate, tricyclodecaneacrylate ortricyclodecanemethacrylate is most desired.

The foregoing epoxy resin (C) which contains at least one compoundhaving one or more epoxy groups in one molecule is a component whichpermits the said resin composition to exhibit highly sensitive andsatisfactory curability in the presence of the foregoing polymerizationinitiator (E) with the action of an active energy ray and in additionthereto, imparts better adhesiveness to a substrate, water resistance,resistance against chemicals, dimensional stability, etc., to theresulting cured film constituted of the said resin composition, when itis formed by applying the said resin composition in liquid state on asubstrate of glass, plastics, ceramics, etc., followed by curing, orwhen it is used in the form of a dry film adhered onto a substrate.

There is not a particular limitation for the epoxy resin (C) as long asit is an epoxy resin that contains at least one kind of compound havingone or more epoxy groups in one molecule.

However, in order for the resulting resin cured film from the resincomposition to have desired resistance against chemicals, mechanicalstrength and high durability as a structural member, in order to improvethe resolution of a pattern comprising the resin cured film to be formedon a substrate and also in order to improve the work efficiency at thetime of forming various patterns comprising the resin cured film on asubstrate, it is desired to use an epoxy resin containing at least onecompound having two or more epoxy groups in one molecule.

Examples of such an epoxy resin containing two or more epoxy groups inone molecule include polyfunctional epoxy resins including epoxy resinsas representd by bisphenol A type, novolac type and alicyclic type, orbisphenol S, bisphenol F, tetrahydroxyphenylmethane tetraglycidyl ether,resorcinol diglycidyl ether, glycerine triglycidyl ether,pentaerythritol triglycidyl ether, isocyanuric acid triglycidyl ether,epoxyurethane resins represented by the following formula I: ##STR7##(wherein R⁴ represents an alkyl group or an oxyalkyl group, R⁵represents ##STR8## or an alkyl group) and the like, as well as mixturesof two or more of them.

Specific examples of these polyfunctional epoxy resins include those asmentioned in the following. That is, the bisphenol A type epoxy resinsmay include, for example, Epicoat 828, 834, 871, 1001 and 1004 (tradenames, produced by Shell Chemical Co.), DER 331-J, 337-J, 661-J, 664-Jand 667-J (-produced by Dow Chemical Co.), Epicrone 800 (trade name,produced by Dainippon Ink Kagaku K. K.), etc. The novolac type epoxyresins may include, for example, Epicoat 152, 154 and 172 (trade names,produced by Shell Chemical Co.), Araldite EPN 1138 (trade name, producedby Ciba Geigy Co.), DER 431, 438 and 439 (trade names, produced by DowChemical Co.), etc. The alicyclic epoxy resins may include, for example,Araldite CY-175, -176, -179, -182, -184 and -192 (trade names, producedby Ciba Geigy Co.), Chissonox 090, 091, 092, 301 and 313 (trade names,produced by Chisso K. K.), CYRACURE 6100, 6110 and 6200 and ERL 4090,4617, 2256 and 5411 (trade names, produced by Union Carbide Co.), etc.The polyglycidyl ethers of aliphatic polyhydric alcohol may include, forexample, ethyleneglycol diglycidyl ether, polyethyleneglycol diglycidylether, propyleneglycol diglycidyl ether, polypropyleneglycol diglycidylether, neopentylglycol diglycidyl ether, 1,6-hexanediol diglycidylether, glycerine diglycidyl ether, trymethylolpropane triglycidyl ether,diglycidyl ether of hydrogenated bisphenol A, 2,2-dibromoneopentylglycoldiglycidyl ether, etc. The. polyglycidyl ethers derived from aromaticpolyhydric alcohol may include, for example, diglycidyl ethers of anaddition product of bisphenol A added with 2 to 16 mols ofalkyleneoxide, diglycidyl ethers of an addition product of bisphenol Fadded with 2 to 16 mols of alkyleneoxide, diglycidyl ethers of anaddition product of bisphenol S added with 2 to 16 mols ofalkyleneoxide.

As the foregoing compound having an epoxy group in one molecule, therecan be mentioned olefine oxides, octylene oxide, butyl glycidyl ether,glycidyl methacrylate, acryl glycidyl ether, styrene oxide, phenylglycidyl ether n-butylphenolglycidyl ether, 3-pentadecylphenyl glycidylether, cyclohexane vinyl monoxide, α-pinene oxide, glycidyl esters oftert-carboxylic acids, and mixtures of these compounds.

The monofunctional epoxy resins including the above compounds may beselectively used alone or in combination with the foregoingpolyfunctional epoxy resins.

The foregoing monomer (D) having an ethylenically unsaturated bond to beused in the resin composition is a component for permitting the saidcomposition to exhibit curability with an active energy ray,particularly imparting excellent sensitivity to an active energy ray tothe said composition, similarly as the above-mentioned half-esterifiedepoxy resin component (C). The said monomer (D) should preferably have aboiling point of 100° C. or higher under atmospheric pressure, havingpreferably two or more ethylenically unsaturated bonds, and variousknown monomers curable by irradiation of an active energy ray can beused.

Specific examples of such monomer having two or more ethylenicallyunsaturated bonds include (a) acrylic acid esters of methacrylic acidesters of polyfunctional epoxy resins having two or more epoxy groups inone molecule, (b) acrylic acid esters or methacrylic acid esters ofalkyleneoxide addition products of polyhydric alcohols (c) polyesteracrylates having acrylic acid ester group at the terminal ends of themolecular chains of polyesters having molecular weights of 500 to 3000comprising dibasic acid and dihydric alcohol, (d) the reaction productsbetween polyisocyanates and acrylic acid monomers having hydroxylgroups. The above monomers (a)-(d) may be urethane-modified productshaving urethane bonds in the molecules.

Examples of the monomer belonging to (a) include acrylic acid ormethacrylic acid esters of polyfunctional epoxy resins to be used forformation of the foregoing half-esterified epoxy resin component (C).

Examples of the monomer belonging to (b) include ethyleneglycol di(meth)acrylate, diethyleneglycol di(meth)acrylate, polyethyleneglycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, polyethyleneglycoldi(meth)acrylate, pentaerythritol tri(meth)acrylate and the like, andthose known under the trade names of KAYARAD HX-220, HX-620, D-310,D-320, D-330, DPHA, R-604, DPCA-20, DPCA-30, DPCA-60, DPCA-120 (allproduced by Nippon Kayaku K. K.), and also those known under the tradenames of NK ester BPE-200, BPE-500, BPE-1300, A-BPE-4 (all produced byShin Nakamura Kagaku K. K.), etc., may also be used.

The monomers belonging to (c) may be exemplified by those known underthe trade names of Aronix M-6100, M-6200, M-6250, M-6300, M-6400,M-7100, M-8030, M-8060, M-S8100 (all produced by Toa Gosei Kagaku K.K.). Examples of the monomer belonging to (c) and having urethane bondsof polyester include those known under the trade names of Aronix M-1100,Aronix M-1200, (both produced by Toa Gosei Kagaku K. K.).

The monomers belonging to (d) may include the reaction products betweenpolyisocyanate such as tolylene diisocyanate, isophorone diisocyanate,hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysinediisocyanate, diphenylmethane diisocyanate or the like with a hydroxylcontaining acrylic monomer, and it is possible to use the reactionproducts having (meth)acrylic acid esters containing hydroxyl group(s)added to polyisocyanate compounds known under the trade names ofSumidule N (buret derivative of hexamethylene diisocyanate), Sumidule L(trimethylolpropane modified product of tolylene diisocyanate) (allproduced by Sumitomo Bayer Urethane K. K.), etc. The hydroxyl containingacrylic monomer as herein mentioned may include typically (meth)acrylicacid esters, preferably hydroxyethyl (meth)acrylate, hydroxypropyl(meth)acrylate. It is also possible to use other acrylic monomerscontaining hydroxyl group(s), particularly those represented by theforegoing formula x to be used for the graft chains in the case of theforegoing graft copolymerized polymer (A).

In addition to the monomers having two or more ethylenically unsaturatedbonds as mentioned above, it is also possible to use monomers havingonly one ethylenically nnsaturated bond as mentioned below together withthese monomers.

To exemplify such monomers having one ethylenically unsaturated bond,there may be included, for example, carboxyl containing unsaturatedmonomers such as acrylic acid, methacrylic acid or the like; glycidylcontaining unsaturated monomers such as glycidyl acrylate, glycidylmethacrylate or the like; C₂ -C₈ hydroxyalkyl esters of acrylic acid ormethacrylic acid such as hydroxyethyl acrylate, hydroxyethylmethacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate or thelike; monoesters of acrylic acid or methacrylic acid withpolyethyleneglycol or polypropyleneglycol such as polyethyleneglycolmonoacrylate, polyethyleneglycol monomethacrylate, polypropyleneglycolmonoacrylate, polypropyleneglycol monomethacrylate or the like; C₁ -C₁₂alkyl or cycloalkyl esters of acrylic acid or methacrylic acid such asmethyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate,butyl acrylate, hexyl acrylate, octyl acrylate, lauryl acrylate,cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, propylmethacrylate, isopropyl methacrylate, butyl methacrylate, isopropylmethacrylate, butyl methacrylate, hexyl methacrylate, octylmethacrylate, lauryl methacrylate, cyclohexyl methacrylate or the like;other monomers such as styrene, vinyltoluene, methylstyrene, vinylacetate, vinyl chloride, vinyl isobutyl ether, acrylonitrile,acrylamide, methacrylamide, acrylic acid or methacrylic acid adduct ofalkylglycidyl ether, vinylpyrrolidone, dicyclopentenyloxyethyl(meth)acrylate, ε-caploractone-modified hydroxyalkyl(meth)acrylate,tetrahydrofurfulyl acrylate, phenoxyethyl acrylate; and others.

By use of the above monomer having ethylenically unsaturated bonds, highsensitivity and satisfactory curability to an active energy ray can beimparted to the resin composition for formation of a resin cured film.

The foregoing polymerization initiator (E) capable of generating a Lewisacid with irradiation of an active energy ray to be used in the activeenergy-ray-curing resin composition in this invention is a component forcuring the half-esterificated epoxy resin (C) as mentioned above withthe action of the Lewis acid, which permits the said resin compositionof exhibit a high sensitivity and desired curability to an active energyray. As such a polymerization initiator (E) , there may be preferablyused, for example, aromatic onium salt compounds having photosensitivitycontaining an element belonging to the groups VIa as disclosed inJapanese Patent Publication No. 52-14278 or aromatic onium saltcompounds having photosensitivity containing an element belonging to thegroup Va as shown in Japanese Patent publication No. 52-14279 oraromatic halonium salts having photosensitivity as shown in JapanesePatent publication No. 52-14277. These aromatic onium salt compounds oraromatic halonium salts all have the characteristic of curing thehalf-esterificated epoxy resin (C) by releasing a Lewis acid withirradiation of an active energy ray.

The aromatic onium salt compounds having photosensitivity of the elementbelonging to the group VIa or the group Va may include typically thecompounds of the following formula II:

    [(R.sup.6).sub.a (R.sup.7).sub.b (R.sup.8).sub.c X].sub.d.sup.+ [MQ.sub.e ].sup.-(e-f)                                              (II)

(wherein R⁶ is a monovalent organic aromatic group, R⁷ is a monovalentorganic aliphatic group selected from alkyl groups, cycloalkyl groupsand substituted alkyl groups, R⁸ is a polyvalent organic group forconstituting heterocyclic or fused ring structure selected fromaliphatic groups and aromatic groups, X is an element belonging to thegroup VIa selected from sulfur, selenium and tellurium or an elementbelonging to the group Va selected from nitrogen, phosphorus, arsenic,antimony and bismuth, M is a metal or metalloid and Q is halogen, a isan integer of 0 to 3 when X is an element belonging to the group VIa oran integer of 0 to 4 when X is an element belonging to the group Va, bis an integer of 0 to 2, c is an integer of 0 or 1 when X is an elementbelonging to the group VIa or an integer of 0 to 2 when X is an elementbelonging to the group Va, f is an integer of 2 to 7 representing thevalence of M, e is an integer which is greater than f but not more than8, and the sum of a, b and c is 3 when X is an element belonging to thegroup VIa or 4 when X is an element belonging to the group Va, andd=e-f).

On the other hand, the photosensitive aromatic halonium salt may beexemplified by the following formula III:

    [(R.sup.9).sub.g (R.sup.10).sub.h X].sub.i.sup.+ [MQ.sub.j ].sup.-(k-1)(III)

(wherein R⁹ is a monovalent aromatic organic group, R¹⁰ is a divalentaromatic organic group, X is halogen, M is a metal or metalloid and Q ishalogen, respectively, g is an integer of 0 or 2 and h is an integer of0 or 1, with the sum of g and h being equal to 2 or the valence of X, ibeing equal to k-1, j is an integer of 2 to 7 which is equal to thevalence of M, and k is an integer greater than one but up to 8).

Specific examples of the photosensitive aromatic onium salt compoundscontaining an element belonging to the group VIa or the group Va mayinclude the photosensitive aromatic onium salts of the elementsbelonging to the group VIa as shown below: ##STR9## and photosensitivearomatic onium salts of the elements belonging to the group Va as shownbelow: ##STR10##

Specific examples of the photosensitive aromatic halonium salts include,for example: ##STR11##

In addition to the above polymerization initiator (E) generating a Lewisacid, it is possible to use a proper known hardner selected frompolyamines, polyamides, acid anhydrides, boron trifluorideaminecomplexes, imidazoles, complexes of imidazoles with metal salts, in casewhere necessary.

The active energy-ray-curing resin composition to be used formanufacturing a liquid jet recording head according to this invention isone that is cured with irradiation of an active energy ray. In the casewhere there are used a graft copolymerized polymer (A) and/or a linearpolymer (B) respectively having photopolymerizability and an activeenergy ray with a wavelength of 250 nm to 450 nm, it is desired to placea radical polymerization initiator having the properties of beingactivated with the action of an active energy ray, forming organic freeradicals and initiating radical polymerization in the said resincomposition.

Specific examples of such radical polymerization initiators includebenzyl ether: benzoin alkyl ethers such as benzoin isobutyl ether,benzoin isopropyl ether, benzoin-n-butyl ether, benzoin ethyl ether,benzoin methyl ether and the like; benzophenones such as benzophenone,4,4'-bis (N,N-diethylamino)benzophenone benzophenone methyl ether andthe like; anthraquinones such as 2-ethylanthraquinone,2-tert-butylanthraquinone and the like; xanthones such as2,4-dimethylthioxanthone, 2,4-diisopropylthioxathone and the like;acetophenones such as 2,2-dimethoxy-2-phenylacetophenone, α,α-dichloro-4-phenoxyacetophenone, p-tert-butyltrichloroacetophenone,p-tert-butyldichloroacetophenone, 2,2-diethoxyacetophenone,p-dimethylaminoacetophenone and the like; or hydroxycyclohexylphenylketone (e.g., Irugacure 184, produced by Ciba Geigy Co.),1-(4-isopropylphenyl)-2-hydroxy-2-methylpropane-1-on (e.g. Darocure1116, produced by Merck Co.): 2-hydroxy-2-methyl-1-phenylpropane-1-on(e.g. Darocure 1173, -produced by Merck Co.): etc., as preferable ones.

In addition to these radical polymerization initiators, amino compoundsmay be added as the photopolymerization accelerator.

The amino compounds to be used as the photopolymerization acceleratormay include ethanolamine, ethyl-4-dimethylaminobenzoate,2-(dimethylamino)ethylbenzoate, p-dimethylaminobenzoic acid n-amylester,p-dimethylaminobenzoic acid isoamyl ester, etc.

Next, the formulation ratio of the respective components as describedabove may be suitably selected depending on the use site or the usepurpose of the active energy-ray-curing resin composition containingthese components in the liquid jet recording head of the presentinvention.

For example, in a preferred embodiment, the weight ratio of the graftcopolymerized polymer (A) to the linear polymer (B) is desired to besuch that (A):(B) is in the range of from 80:20 to 50:50 in parts byweight.

This situation is an important factor for the active energy-ray-curingresin composition according to this invention to exhibit a desiredadhesiveness to a substrate based on the graft copolymerized polymer (A)and a desired patterning property based on the linear polymer (B).

In addition to the above, the weight ratio of the sum amount of thegraft copolymerized polymer (A) and the linear polymer (B) to the sumamount of the epoxy resin (C) and the monomer having an ethylenicallyunsaturated bond (D) is desired to be such that [(A)+(B)]:[(C)+(D)] isin the range of from 100:50 to 100:200, which the weight ratio of theepoxy resin (C) to the monomer having an ethylenically unsaturated bond(D) is desired to be such that (C):(D) is in the range of from 25:75 to75:25.

Further, the weight ratio of the sum amount of the graft copolymerizedpolymer (A), the linear polymer (B), the epoxy resin (C) and the monomerhaving an ethylenically unsaturated bond (D) to the polymerizationinitiator (E) is desired to be such that [(A)+(B)+(C)+(D)]:(E) is in therange of from 100:1 to 100:10 in parts by weight.

In the case where the foregoing radical polymerization initiator (F)and/or the amino compound (G) as a photopolymerization accelerator isused, the addition amount [(F)+(G)] (including the case of (F)=0 or(G)=0) is desired to be such that [(A)+(B)+(C)+(D)]:[(F)+(G)] is in therange of from 100:1 to 100:10.

Further, in the active energy-ray curing resin composition, ifnecessary, there may be also added condensation crosslinking catalysts,thermal polymerization inhibitors, colorants such as dyes, pigments,etc., thermal stabilizers such as hydroquinone, p-methoxyphenol, etc.,close contact accelerators, plasticizers, extender pigments such assilica, talc, etc., leveling agents which give coating adaptability andso on.

For example, as the condensation crosslinking catalyst, sulfonic acidsas represented by p-toluenesulfonic acid, carboxylic acids such asformic acid, etc. may be included. As the thermal polymerizationinhibitor, hydroquinone and derivatives thereof, p-methoxyphenol,phenothiazine, etc. may be included. As the colorant, oil-soluble dyesand pigments can be added within the range which does not substantiallyinterfere with transmission of the active energy ray. As the filler, forhardness elevation of the coating, elevation of coloration, closecontact, mechanical strength, extender pigments, plastic fine particles,etc. used in coating materials in general may be employed. As the closecontact accelerator, there are silane coupling agents as the inorganicsurface modifier, low molecular weight surfactant, etc.

As the solvent to be used when using the above active energy-ray-curingresin composition in a solution, or coating the resin composition on aplastic film and the like which is a film substrate in forming a dryfilm for penetration of the liquid jet recording head of the presentinvention, hydrophilic solvents such as alcohols, glycol ethers, glycolesters, etc. may be included. Of course, it is also possible to usemixtures based primarily on these hydrophilic solvents, optionally mixedsuitably with ketones such as methyl ethyl ketone, methyl isobutylketone, etc.; esters such as ethyl acetate, isobutyl acetate, etc.;aromatic hydrocarbons such as toluene, xylene, etc. and halogenderivatives thereof; aliphatic solvents containing chlorine such asmethylene chloride, 1,1,1-trichloroethane, etc. These solvents can bealso used as the developer of said resin composition.

In preparing the liquid jet recording head of the present invention, theresin composition can be formed into a cured layer on a substrate andthe like according to conventional methods.

For example, the following cases may be included.

(1) The case when a layer comprising a cured coating film is formed on asubstrate, etc.;

The above-mentioned active energy-ray-curing resin composition in liquidstate is imparted onto a substrate, etc. for forming a liquid coatingfilm, and then dried by evaporation. And, the dried coating filmobtained is cured by irradiation of an active energy ray to make a layercomprising a cured coating film.

(2) The case when a layer comprising a cured coating film in shape of adesired pattern is formed on a substrate, etc. (First one);

The above-mentioned active energy-ray-curing resin composition in liquidstate is imparted onto a substrate, etc. for forming a liquid coatingfilm, and then dried by evaporation. And, a laser beam is scanned to adesired pattern on the layer comprising the dried coating film, and acured coating film layer with a desired pattern shape is formed on thesubstrate, etc. by removing the unexposed portion with an appropriatesolvent such as 1,1,1-trichloroethane, etc.

(3) The case when a layer comprising a cured coating film with a desiredpattern shape is formed on a substrate, etc (Second one);

Onto a substrate, etc., the above-mentioned active energy-ray-curingresin composition in liquid state is imparted for forming a liquidcoating film, and subsequently dried by evaporation. On the layercomprising the dried coating film obtained, a photomask having a desiredpattern through which the active energy ray is not transmitted issuperposed, and exposure is effected from above the photomask with theactive energy ray. And, the unexposed portion is removed with anappropriate solvent such as 1,1,1-trichloroethane, etc. to form a layercomprising a cured coating film with a desired pattern shape on thesubstrate, etc.

(4) The case when a photosensitive dry film is formed, and the dry filmis laminated on a substrate, etc.;

The above-mentioned active energy-ray-curing resin in liquid state isimparted onto a polyethylene terephthalate film for formation of aliquid film, and subsequently dried by evaporation to obtain aphotosensitive dry film on the polyethylene terephthalate film. The dryfilm is laminated on a substrate, etc. by conventional lamination methodfor obtaining a laminate. And, the photosensitive dry film laminated onthe substrate, etc. is cured by irradiation with the active energy rayaccording to the same method as the above-described method (1). When thecured photosensitive film is to be formed into a desired pattern, theabove dry film laminated on the support is treated according to the samemethods as (2) or (3) as described above.

When the active energy-ray-curing resin composition contains a monomerrepresented by the above general formula (x), it is desirable to furthereffect condensation curing of the cured film obtained by the methods (1)to (4) as described above by subjecting it to heating treatment at atemperature of 80° C. to 200° C.

In the preparation process of the liquid jet recording head of thepresent invention, as the active energy ray to be used for curing theactive energy-ray-curing resin composition, or pattern exposure onto theresin composition, etc., UV-ray or electron beam already practicallyapplied widely may be employed. As the UV-ray light source, highpressure mercury lamps, ultra-high pressure mercury lamps, metal halidelamps, etc. enriched in light with wavelengths of 250 nm to 450 nm maybe included, and one with a light intensity in the vicinity of 365 nm ofabout 1 mW/cm² to 100 mW/cm² at a practically tolerable distance betweenthe lamp and the material to be irradiated may be preferred. Theelectron beam irradiation apparatus is not particularly limited, but anapparatus having a dose within the range from 0.5 to 20M Rad ispractically suitable.

Referring now to the case of forming the liquid path wall 3H with acured film of the dry film type obtained from the above-mentioned resincomposition as an example, the method for preparing the liquid jetrecording head is to be described.

FIG. 2 to FIG. 6B are schematic diagrams for illustration of thepreparation procedure of the liquid jet recording head of the presentinvention.

For formation of the liquid jet recording head of the present invention,as shown in FIG. 2, discharge energy generating devices 2 such as heatgenerating element, piezoelectric elements, etc. are arranged in adesired number on the substrate 1 of glass, ceramic, plastic or metal,etc. If necessary, for imparting resistance to the liquid for recording,electrical insulation, etc. to the surface of the substrate, saidsurface may be coated with a protective layer of SiO₂, Ta₂ O₅, glass,etc. To the discharge energy generating elements 2 are connectedelectrodes for inputting recording signals, although not shown.

Next, after cleaning and drying at, for example, 80° to 150° C. of thesurface of the substrate 1 obtained via the step shown in FIG. 2, asshown in FIG. 3A and FIG. 3B, the above-described activeenergy-ray-curing resin composition 3 of the dry film type (filmthickness: about 20 μm to 200 μm) is heated to about 40° to 130° C., andlaminated on the substrate surface 1A under the conditions of, forexample, a speed of 0.5 to 0.4 f/min. and pressurization of 1 to 3Kg/cm².

Subsequently, as shown in FIG. 4, after a photomask 4 having a pattern4P with a predetermined shape which does not transmit the active energyray is superposed on the dry film layer 3 provided on the substratesurface 1A, exposure is effected from above the photomask 4.

Alignment between the photomask 4 and the substrate 1 is effected sothat the above elements 2 may be positioned in the liquid path regionsformed finally via the steps of exposure, developing processing, etc.,and can be practiced according to the method in which alignment marksare drawn respectively on the substrate 1 and the mask 4, and alignmentis effected following the marks.

By carrying out thus exposure, the portions other than the regioncovered with the above-mentioned pattern, namely the portion of the dryfilm layer 3 exposed is cured by polymerization to become solventinsoluble, while the portion not exposed remains solvent soluble.

As the active energy ray to be used for this pattern exposure, suitableone may be selected and used from among active energy rays known in theart depending on the kinds of the components of the above-describedactive energy ray curing resin composition, including specifically, forexample, high pressure mercury lamp, ultra-high pressure mercury lamp,metal halide lamp, carbon arc lamp, electron beam, etc.

For example, as the UV-ray light source, high pressure mercury lamp,ultra-high pressure mercury lamp, metal halide lamp, etc. enriched inlight with wavelengths of 250 nm to 450 nm may be included, and one witha light intensity in the vicinity of 365 nm of about 1 mW/cm² to 100mW/cm² at a practically tolerable distance between the lamp and theobject to be irradiated may be preferred. The electron beam irradiationapparatus is not particularly limited, but an apparatus having a dosewithin the range from 0.5 to 20M Rad is practically suitable.

On completion of the pattern exposure of the dry film layer 3, next theexposed dry film 3 is subjected to developing processing by dipping intoa volatile organic solvent such as 1,1,1-trichloroethane, etc., therebydissolving away the unpolymerized (uncured) portion of the dry filmlayer 3 on the substrate 1 which is solvent soluble to form the groovewhich becomes finally the liquid paths 6-2 and the liquid chamber 6-1with the resin cured film 3H remaining on the substrate 1, as shown inFIGS. 5A and 5B.

Next, the cured resin film 3H on the substrate 1 is heated at atemperature of at least 80° C. for about 10 minutes to 3 hours to carryout thermal polymerization. When a thermosetting graft copolymerizedpolymer is used in the resin composition 3, the heating treatment ismade a temperature of at least 100° C. for about 5 to 60 minutes.

In the recording head of this example, description is made about anexample by use of a resin composition of the dry film type, namely insolid state, for formation of the groove which becomes the liquid path6-2 and the liquid chamber 6-1, but the active energy-ray-curing resincomposition which can be used in formation of the recording head of thepresent invention is not only limited solid state, but of course liquidones can be used.

As the method for forming a layer comprising a liquid resin compositionby use of the composition on the substrate, for example, there may beemployed the method by means of squeezy used during preparation of arelief image, namely in which a wall of a height corresponding to thethickness of a coating of a desired composition is provided around thesubstrate, and superfluous resin composition is removed by a squeezy. Inthis case, the viscosity of the resin composition may be appropriately100 cp to 3000 cp. The height of the wall placed around the substrate isrequired to be determined by taking into account the reduction of thesolvents contained in the photosensitive resin composition byevaporation.

When a solid resin composition is used, the method of plastering a dryfilm onto a substrate by heating pressure contact as described above issuitable.

However, in forming the recording head of the present invention, thesolid film type is convenient in handling, or with respect to easy andaccurate control of the thickness.

After having thus formed the groove constituting finally the liquid path6-2 and the liquid chamber 6-1 with the resin cured film 3H, a flatplate 7 which becomes the cover of the groove is bonded to the resincured film 3H with an adhesive to form a bonded product, as shown inFIGS. 6A and 6B.

In the step shown in FIGS. 6A and 6B, as a specific method for providingthe cover 7, there is, for example, the method in which the flat plate 7of glass, ceramic, metal, plastic, etc. is spin coated with an epoxytype adhesive to a thickness of 3 to 4 μm, then preheated to effect theso called B-staging and plastering this onto the cured dry film 3H,followed by main curing of the above-mentioned adhesive layer, etc.However, there may be also employed the method not using an adhesive inwhich the flat plate 7 of a thermoplastic resin such as acrylic resin,ABS resin, polyethylene, etc. is directly thermally fused onto the resincured film 3H.

Also, it is preferable to use the method in which a resin layercomprising the resin composition for formation of a resin cured film inthe present invention is provided on the side to be bonded to the liquidpath of the cover 7 thermally, fused with the resin cured film 3H havingthe liquid paths formed, and then heated by irradiation of an activeenergy ray. That is, this is the method in which the resin compositionfor formation of a resin cured film in the present invention is used asan adhesive.

In FIGS. 6A and 6B, 6-1 shows the liquid chamber, 6-2 the liquid paths,8 the thru-hole for connecting the feeding pipe (not shown) for feedingthe liquid for recording into the liquid chamber from the outside of therecording head to the inside.

Thus, after completion of bonding of the resin cured film 3H provided onthe substrate 1 with the flat plate 7, the bonded product is cut alongC--C corresponding to the downstream side of the liquid path 6-2 shownin FIGS. 6A and 6B to form orifices for discharging the liquid forrecording which are openings of the liquid paths at the cut surface.

This step is done for optimizing the interval between the dischargeenergy generating device 2 and the orifice 9, and here the region to becut may be suitably selected. In carrying out this cutting, the dicingmethod, etc. conventionally employed in semiconductor industries can beemployed.

The downstream portion of the liquid path as mentioned in the presentinvention refers to the downstream region in the flow direction of theliquid for recording when recording is performed by use of a recordinghead, specifically the portion of the liquid path downstream of theposition where the discharge energy generating device 2 is provided.

When cutting is completed, the cut surface is polished to be smoothened,and the feeding pipes (not shown) are mounted on the thru-hole 8 tocomplete the liquid jet recording head as shown in FIGS. 1A and 1B.

In the example as described above, after formation of the resin curedfilm 3H on the substrate 1, the cover 7 is bonded thereto, but it isalso possible to form the resin cured film 3H on the side of the cover 7and then bond it to the substrate 1. Also, the liquid paths 6-2 and theliquid chamber 6-1 may be separately formed.

A preferred example of a recording apparatus employing the recordinghead in accordance with the present invention is described by referringto the drawing.

FIG. 11 is a perspective view schematically showing an embodiment of theliquid ejection recording apparatus of the present invention. In FIG.11, reference numeral 119 designates recording paper. The recordingpaper 119 is moved on a platen 115 at a predetermined speed in thesubsidiary scanning direction (the direction of arrow A) by a paperfeeding roller 114 and a pinch roller 116. Reference numeral 117 and 118denote pulleys supported on respective shafts and rotated by a drivesource (not shown). A carriage driving belt 112 is passed over thepulleys 117 and 118.

A carriage 113 is integrally fixed to the carriage driving belt 112. Thecarriage 113 is guided by guide shafts 108 and 111 and is reciprocallymovable in the major scanning directions (the directions of arrow B) bythe rotation of the pulleys 117 and 118 a roller 120 adapted to roll onthe guide shaft 111 is disposed on the underside of the carriage 113.

A connector 122 electrically connected to flexible wiring 121 isdisposed substantially in the central portion of the carriage 113, and ahead aligner 123 or aligning the liquid ejection recording head(hereinafter referred to as the recording head) 101 when the wires ofthe recording head 101 are connected and fixed to the connector 122 isvertically provided on the carriage 113. Accordingly, the recording head101 is removable from the carriage 113 by the connector 122. Also, asensor 124 for detecting the home position of the carriage 113 isprovided.

The recording head 101 has a substrate 106, which in turn has thereondischarge ports 102 for discharging ink droplets which are flyingdroplets, a liquid flow path constituting portion 103 for constitutingliquid flow paths communicating with the discharge ports 102 and havingenergy generating members such as heat generating elements for formingflying ink droplets, and an ink chamber for storing therein ink to besupplied to the liquid flow paths. To the energy generating members ofthe recording head 101, a driving voltage is supplied from a drivingvoltage generating circuit 129 (not shown) through the connector 122 andthe flexible wiring 121 and also, a discharge control signal forcontrolling the discharge of ink droplets from the discharge ports 102.

The present invention is described in more detail by referring toSynthesis Examples and Examples. However, the present invention is notlimited to the following Examples at all.

SYNTHESIS EXAMPLE 1

The following components constituting the active energy-ray-curing resincomposition to be used for preparation of the liquid jet recording headof the present invention were prepared.

Preparation of a Graft Copolimerized Polymer (A)

Radical chain transfer polymerization of 80 parts by weight of2-hydroxyethylmethacrylate and 20 parts by weight of butylacrylate wascarried out using thioglycollic acid as the chain transferring agent andazobisisobutyronitrile as the polymerization initiator to obtain anoligomer having a carboxyl group at the terminal end of the molecularchain.

This oligomer was reacted with glycidylmethacrylate to obtain amacromonomer having a methacryloyl group at one terminal end of themolecular chain. The result of the measurement by the known GPC methodgave a value of about 3,000 for the number average molecular weight ofthe resultant macromonomer.

Solution polymerization of 30 parts by weight of the said macromonomerand 70 parts by weight of methylmethacrylate was carried out in methylcellosolve solvent to thereby obtain a graft copolymerized polymerhaving a weight average molecular weight of about 40,000 and a numberaverage molecular weight of about 5,500.

A Linear Polymer (B)

There was provided a linear acrylic copolymer obtained by polymerizingmethylmethacrylate. This linear acrylic copolymer is one that has anumber average molecular weight of about 70,000 and a weight averagemolecular weight of about 250,000.

An Epoxy Resin (C)

There were provided the following two epoxy resins 1) and 2):

1) Epicoat 152 (trade name, produced by Yuka Shellepoxy K. K.)(epoxyresin of cresol novolac type: eopoxy equivalent of 172-179)

2) Cell oxide 2021 (trade name, produced by Daiseru Kagaku K. K.)(epoxyresin of alicyclic type: epoxy equivalent of 128-145)

A monomer Having an Ethylenically Unsaturated Bond (D)

There was provided the following acrylic ester: acrylic ester (100%esterificated) of Epicoat 828 (trade name, produced by Yuka ShellepoxyK. K.)(epoxy resin of bisphenol A type: epoxy equivalent of 183-193)

A Polymerization Initiator (E)

There was provided bis-[4-(diphenylsulfonyl)phenyl]sulfide-bis-hexafluoroantimonate represented by the foregoing structuralformula n.

A Photopolymerization Initiator (F) for the Above Monomer (D)

There was provided IRUGACURE 651 (trade name, produced by Chiba GeigyCo.)

The above components were well mixed by the weight ratios as below shownin accordance with the conventional mixing technique to thereby obtainthe active energy-ray-curing resin composition in liquid state.

    ______________________________________                                        Component       Parts by weight                                               ______________________________________                                        (A)             50                                                            (B)             50                                                            (C)-1           50                                                            (C)-2           20                                                            (D)             50                                                            (E)             8                                                             (F)             10                                                            methyl cellosolve                                                                             200                                                           methylethyl ketone                                                                            100                                                           ______________________________________                                    

Next, a part of the thus obtained resin composition in liquid state wasapplied onto a polyethyleneterephthalate film (Lumilar T type) of 25 μmusing reverse coater, followed by drying to obtain a dry film having athickness of about 40 μm.

To the dryed coated layer was further laminated a stretched polyethylenefilm of 40 μm as a cover film, thereby having obtained a laminate of thestructure that the active energy-ray-curing resin composition layer as adry film (thickness: 40 μm) was sandwiched between two films.

Also, the same process was repeated to obtain a laminate except that theapplication by a reverse coater was effected so as to form a dry filmhaving a thickness of 80 μm.

EXAMPLE 1

By use of the dry film prepared in Synthesis example 1, following thesteps in FIG. 1 to FIG. 6 as described previously in the specification,preparation of an on-demand type liquid jet recording head of the typeshown in FIG. 7H having 10 heat-generating devices [Hafnium boride(HfB₂)] and orifices provided corresponding to said heat-generatingdevices (orifice dimensions: 80 μm×120 μm, arrangement pitch 0.200 mm)was practiced as described below. The recording heads of the same shapewere trially made each in number of 30.

First, a plurality of heat-generating devices were arranged atpredetermined positions on a substrate comprising silicon, andelectrodes for application of recording signals were connected to these.

Next, a SiO₂ layer (thickness 1.0 μm) as the protective layer wasprovided on the substrate surface having heat-generating devicesarranged thereon, and after the surface of the protective layer wascleaned and dried, the dry film with a thickness of 80 μm obtained inSynthesis example 1 heated to 100° C. was laminated on the protectivelayer by use of a rubber roll under the conditions of a roll temperatureof 100° C. and a circumferential speed of 1.0 m/min, while peeling offthe polyethylene film

Subsequently, with a photomask having a pattern corresponding to theliquid path and the liquid chamber superposed on the dry film providedon the substrate surface, registration was performed so that the abovedevices could be provided in the liquid path to be finally formed,followed by vacuum adhesion, and then exposure was effected from abovethe photomask on the dry film by use of a ultra-high pressure mercurylamp with a UV-ray intensity around 365 nm of 10 mW/cm² and a highparallel degree with a collimatlon argument of 3° for 20 seconds.

Next, after completion of exposure, the polyethylene terephthalate filmwas peeled off from the dry film on the substrate, and then said dryfilm was subjected to spray developing processing with1,1,1-trichloroethane (trade name Eterner Nu) at 20° C. for 50 seconds,thereby dissolving away the unpolymerized (uncured) portion of the dryfilm to form a groove which becomes finally the liquid path and theliquid chamber with the wall comprising the cured dry film remaining onthe substrate.

After completion of developing processing, post-exposure (UV post-cure)was effected on the cured dry film on the substrate with a ultra-highpressure mercury lamp under the same conditions as previously used forpattern exposure for 5 minutes, and further heating treatment wasperformed to apply post-curing treatment at 150° C. for 15 minutes.

Thus, a groove which becomes the liquid path and the liquid chamber wasformed with a wall comprising the cured dry film on the substrate.

On the other hand, as described below, a ceiling plate covering over thewall comprising the cured dry film formed on the above-mentionedsubstrate was formed.

The dry film with a film thickness of 40 μm obtained in Synthesisexample 1 heated to 100° C. was laminated by use of a rubber roll underthe conditions of a roll temperature of 100° C. and a circumferentialspeed of 1.0 m/min. on a glass plate which becomes the ceiling platewhile peeling off the polyethylene film.

Subsequently, with a photomask having a pattern corresponding to theshape of the liquid chamber superposed on the dry film provided on theglass plate, registration was effected, followed by vacuum adhesion, andthen exposure was effected from above the photomask on the dry film byuse of a ultra-high pressure mercury lamp with a UV-ray intensity around365 nm of 10 mW/cm² and a high parallel degree with a collimationargument of 3° for 35 seconds.

After exposure, the polyethylene terephthalate film remaining on the dryfilm on the glass plate was peeled off, and developing processing,mercury lamp irradiation treatment and heating treatment were appliedunder the same conditions as in the step of forming the liquid path andthe liquid chamber on the substrate as described above, to form aceiling equipped with the liquid chamber.

Then, on the dry film surface side of the ceiling thus formed, theliquid active energy-ray-curing resin composition obtained in Synthesisexample 1 was coated by a roll coater, dried in hot air at 80° C. for 5minutes to form a resin layer for adhesion with a thickness of 3 μm, andsaid ceiling plate was plastered on the upper surface side of the cureddry film on the above substrate with said resin layer interposed.Further, the substrate was bonded under pressurization to the flatplate, followed further by irradiation of a UV-ray at 50 mW/cm² for 60seconds from the ceiling plate side to cure completely the resin layerfor adhesion, thereby effecting fixing by adhesion of the substrate andthe ceiling plate to form a bonded product.

Subsequently, the place downstream side of the liquid path of the bondedproduct, namely 0.150 mm downstream side from the position where thedischarge energy generating device was located, was cut vertically tothe liquid path by means of a commercially available dicing saw (tradename: DAD 2H/6 Model, Disco) to form an orifice for discharging theliquid for recording.

Finally, the cut surface was washed and then dried, followed further bypolishing of the cut surface to effect smoothening and mounting of thefeeding pipe of the liquid for recording on the thru-hole to completethe liquid jet recording head. The recording heads obtained were allfound to be excellent dimensional precision having liquid paths andliquid chambers reproducing faithfully the mask pattern. In thisconnection, the orifice dimensions were within the ranges oflongitudinally 50±5 μm, laterally 70±5 μm, and the orifice pitch withinthe range of 120±5 μm. The quality and the durability during prolongeduse of the recording heads thus prepared were tested as described below.

First, for the recording heads obtained, the durability test ofperforming the dipping treatment in the liquids for recording comprisingthe following compositions at 60° C. for 1000 hours (the environmentalconditions comparable with those during the actual prolonged use ofrecording heads) was practiced.

Liquid Components for Recording

1) H₂ O/diethylene glycol/1,3-dimethyl-2-imidazolidinone/C.I. DirectBlue 86*¹ (=57/30/10/3 parts by weight) pH=8.0

2) H₂ O/diethylene glycol/N-methyl-2-pyrrolidone/C.I. Direct Black 154*²(=55/30/10/5 parts by weight) pH=9.0

3) H₂ O/diethylene glycol/polyethylene glycol#400/N-methyl-2-pyrrolidone/C.I. Direct Yellow 86*³ (=65/10/10/10/5parts by weight) pH=7.0

4) H₂ O/ethylene glycol/triethylene glycol/triethylene glycol monomethylether/C.I. Food Black 2*⁴ (=67/10/15/5/3 parts by weight) pH=10.0.

The notes *1 to *4 are water-soluble dyes, and sodium hydroxide wasemployed for pH control.

After the durability test, for each of the heads practiced with thetest, the bonding state of the cured dry film to the substrate and thecover was observed. As the result, no peel-off and damage was recognizedat all in all the recording heads, thus exhibiting good close contact.

Next, separately, for 10 recording heads obtained, each head was mountedon the recording apparatus shown in FIG. 11, and the printing test waspracticed, which performed printing by use of the liquid for recordingas mentioned above by applying a recording signal of 10⁸ pulses on therecording head continuously for 14 hours. Concerning either recordinghead, immediately after initiation of printing and after elapse of 14hours, substantially no lowering in performance was recognized in bothdischarging performance and print state of the liquid for recording,thus evidencing a recording head excellent in durability.

As described above, the active energy-ray-curing resin composition usedin the constitution of the liquid jet recording head of the presentinvention comprises the graft copolymerized component (A) as theconstituent and therefore has sufficient adhesion to various memberswithout addition of an additive, and also contains the linear polymer(B) as the constituent and is therefore excellent in developingcharacteristics during pattern formation. Also, its cured film hassufficient chemical resistance and durability.

Further, the composition employs the graft copolymerized polymer and thelinear polymer as the polymeric substances which are its constituents incombination, and therefore a coating with solvent resistance to thedeveloper is obtained with less active energy ray irradiation ascompared with the case when employing only the graft copolymerizedpolymer alone as the polymeric substance. As the result, the propertiesof the patterning process are improved, such that sensitivity andresolution can be improved and pattern formation can be effected withoutbeing influenced by the kinds or the states of the members, etc.,whereby the working conditions width can be expanded.

Since said composition contains both of a monomer having anethylenically unsaturated bond and an epoxy resin as the activeenergy-ray-curing components, it may be considered that two kinds ofreactions proceed simultaneously during curing with an active energy rayirradiation, whereby a network structure communicated to each other isformed. By this, the properties which are not merely stiff but enrichedin toughness can be obtained, consequently giving good performances suchas excellent adhesion, mechanical strength, no penetration of ink jetink, little dissolution ink jet ink, etc. As the recording head, it isrendered possible to prepare a high density nozzle having practicaldurability. From the above-mentioned two facts, the recording head is byfar superior in durability both mechanically and chemically.

Therefore, the recording head of the present invention which employs thecured product of the composition as at least a part of its constitutionis inexpensive and precise, and becomes higher in reliability anddurability. Also, by formation of the liquid path wall with the curedfilm of the composition, a recording head having the liquid path finelyworked with good precision and good yield can be obtained.

Further, the recording head of the present invention, by having theconstitution as described above, becomes higher in reliability andexcellent in durability also when formed into a multi-orifice type.

We claim:
 1. A process for producing a liquid jet recording headcomprising a discharge opening for discharging a recording liquid, aliquid path communicating with the discharge opening and a dischargeenergy generating element aligned with the liquid path for generating anenergy to discharge the recording liquid from the discharge opening,said process comprising the steps of:applying an active energy-curingresin composition onto at least a part of a surface of a first memberfor forming a wall of the liquid path; exposing the applied activeenergy-ray-curing resin composition to an active energy ray selectedfrom the group consisting of an ultraviolet ray having an intensity of 1mW/cm² to 100 mW/cm² and an electron beam with an intensity of 0.5M Radto 20M Rad; and providing a second member on the exposed activeenergy-ray-curing resin composition; wherein said first member or saidsecond member has a discharge energy generating element provided thereonand the active energy-ray-curing resin composition comprises(a) a graftcopolymerized polymer having a number average molecular weight of 5,000or more and a weight average molecular weight of 50,000 or less, whichcomprises a trunk chain composed mainly of structural units derived fromat least one monomer selected from the group consisting of alkylmethacrylates, acrylonitrile and styrene and has graft chains havingstructural units derived from at least one monomer selected from thegroup consisting of monomers represented by the following formulae (x)and (y): ##STR12## wherein R¹ is a hydrogen atom or an alkyl orhydroxyalkyl group having 1 to 3 carbon atoms, R² is a hydrogen atom oran alkyl or acyl group having 1 to 4 carbon atoms which may have hydroxygroups, R³ is an alkyl group having 2 to 6 carbon atoms, ahalogen-substituted alkyl group having 2 to 6 carbon atoms, analkylether group represented by the formula: ##STR13## wherein 2≦m+n≦6,n≠0, m≠0, or a phenylalkyl group represented by the formula: ##STR14##wherein 2≦m+n≦4, or the case where n=0 or m=0 is contained; (B) a linearpolymer having a number average molecular weight of 50,000 or more and aweight average molecular weight of 350,000 or less and having a glasstransition temperature of 60° C. or higher, which comprises (i)structural units derived from at least one monomer selected from thegroup consisting of methyl methacrylate, ethyl methacrylate, isobutylmethacrylate, t-butyl methacrylate, benzyl methacrylate, acrylonitrile,isobornyl methacrylate, isobornyl acrylate, tricyclodecane acrylate,tricyclodecane methacrylate, tricyclodecaneoxyethyl methacrylate,styrene, dimethylaminoethyl methacrylate and cyclohexyl methacrylate,and (ii) from 5 to 30 mol % of structural units derived from at leastone monomer selected from the group consisting of said monomersrepresented by the formula (x) and the monomers represented by theformula (y); (C) an epoxy resin which contains at least one compoundhaving one or more epoxy groups in one molecule; (D) a monomer having anethylenically unsaturated bond; and (E) a photopolymerization initiatorcapable of generating a Lewis acid by irradiation with an active energyray.
 2. The process according to claim 1, wherein the exposure with theactive energy ray is carried out according to a desired pattern.
 3. Theprocess according to claim 2, wherein the exposure with the activeenergy ray is carried out by scanning the active energy-ray-curing resincomposition with the active energy ray.
 4. The process according toclaim 2, wherein the exposure with the active energy ray is carried outvia a photomask.
 5. The process according to claim 1, further comprisinga step of heat treatment at a temperature of 80° C. to 200° C. after theexposing step.
 6. The process according to claim 1, wherein the activeenergy-ray-curing resin composition is liquid.
 7. The process accordingto claim 6, wherein the active energy-ray-curing resin composition has aviscosity of 100 cp to 3000 cp.
 8. The process according to claim 1,wherein the first member has a planar shape.
 9. The process according toclaim 1, wherein the second member has a planar shape.
 10. The processaccording to claim 1, further comprising a step of developing theexposed active energy-ray-curing resin composition.
 11. The processaccording to claim 1, further comprising a step of developing theexposed active energy-ray-curing resin composition before the step ofproviding the second member.
 12. The process according to claim 1,wherein the discharge energy generating element is provided on the firstmember.
 13. The process according to claim 12, wherein the activeenergy-ray-curing resin composition is applied onto the first memberprovided with the discharge energy generating element, the exposure withthe active energy ray is carried out in a manner not corresponding tothe position of the discharge energy generating element, the irradiatedactive energy-ray-curing resin composition is developed, whereby a partof the active energy-ray-curing resin composition is removedcorresponding to the position of the discharge energy generatingelement.
 14. The process according to claim 1, wherein the dischargeenergy generating element is provided on the second member.
 15. Theprocess according to claim 1, wherein the step of applying the activeenergy-ray-curing resin composition is carried out at a temperature of40° C. to 130° C.
 16. The process according to claim 1, wherein theactive energy-ray-curing resin composition is solid.
 17. The processaccording to claim 6, wherein the active energy-ray-curing resincomposition is solidified by applying and drying the liquid activeenergy-ray-curing resin composition.
 18. The process according to claim1, wherein the discharge energy generating element is a heat generatingelement.
 19. The process according to claim 1, wherein the weight ratioof the graft copolymerized polymer (A) to the linear polymer (B) is in arange of (A):(B)=80:20 to 50:50.
 20. The process according to claim 19,wherein the ratio of the total weight of the graft copolymerized polymer(A), the linear polymer (B), the epoxy resin (C) and the monomer (D) tothe weight of the photopolymerization initiator (E) is in a range of((A)+(B)+(C)+(D)):(E)=100:1 to 100:10.
 21. The process according toclaim 19, wherein the ratio of the total weight of the graftcopolymerized polymer (A) and the linear polymer (B) to the total weightof the epoxy resin (C) and the monomer (D) is in a range of((A)+(B)):((C)+(D))=100:50 to 100:200.
 22. The process according toclaim 21, wherein the ratio of the total weight of the graftcopolymerized polymer (A), the linear polymer (B), the epoxy resin (C)and the monomer (D) to the weight of the photopolymerization initiator(E) is in the range of ((A)+(B)+(C)+(D)):(E)=100:1 to 100:10.
 23. Theprocess according to claim 21, wherein the ratio of the epoxy resin (C)to the monomer (D) is in a range of (C):(D)=25:75 to 75:25.
 24. Theprocess according to claim 1, wherein the ratio of the total weight ofthe graft copolymerized polymer (A) and the linear polymer (B) to thetotal weight of the epoxy resin (C) and the monomer (D) is in a range of((A)+(B)):((C)+(D))=100:50 to 100:200.
 25. The process according toclaim 24, wherein the ratio of the total weight of the graftcopolymerized polymer (A), the linear polymer (B), the epoxy resin (C)and the monomer (D) to the weight of the photopolymerization initiator(E) is in the range of ((A)+(B)+(C)+(D)):(E)=100:1 to 100:10.
 26. Theprocess according to claim 24, wherein the ratio of the epoxy resin (C)to the monomer (D) is in a range of (C):(D)=25:75 to 75:25.
 27. Theprocess according to claim 1, wherein the ratio of the total weight ofthe graft copolymerized polymer (A), the linear polymer (B), the epoxyresin (C) and the monomer (D) to the weight of the photopolymerizationinitiator (E) is in a range of ((A)+(B)+(C)+(D)):(E)=100:1 to 100:10.